The appearance and construction of illuminated point of purchase signs are many and varied. For a sign manufacturer and supplier, that has called for a need to tool for, manufacture, stock and supply a large number of different parts for meeting varied requirements and that leads to substantial expenses.
Often, illuminated signs are meant to be hung against a store wall or the like. When something goes wrong, for instance when a lamp or starter burns out, or when the sign servicer or proprietor wishes to change the sign face or change the message conveyed thereby, it is often necessary to demount the sign from the wall and to substantially disassemble it. This is cumbersome and raises the risk that the sign will be broken or suffer from all this handling. Too, the difficulty of changing or fixing such signs tends to cause their servicers or proprietors to let them hang in a broken or obsolete condition for long times after the need to do something about their condition has first been noticed.